The present invention relates to inductive coupling and more particularly to systems and methods for providing multiple ranges of inductive power.
Systems for providing wireless power using the principles of electromagnetic inductive have been available for many years. Conventional systems have met with limited success as a result of practical limitations on pre-existing inductive technology. For example, to provide reasonably efficient operation, conventional inductive systems typically require close and precise alignment between the primary coil and the secondary coil, as well as a high degree of coordinated tuning between the electronics in the inductive power supply and the electronics in the remote device. These problems are complicated by the fact that different remote devices may require vastly different amounts of power. For example, a cell phone is likely to have different power requirements than a laptop or a kitchen appliance.
Some advances have been made that allow an inductive power supply to adjust and account for some differences between remote devices. U.S. Pat. No. 6,825,620 to Kuennen et al discloses an inductive power supply system that has the ability to adjust its operation to correspond with the operating parameters of various loads. U.S. Pat. No. 6,825,620 to Kuennen et al, which is entitled “Inductively Coupled Ballast Circuit” and was issued on Nov. 30, 2004, and is incorporated herein by reference. U.S. patent application Ser. No. 11/965,085 discloses an inductive power supply system that has the ability to identify the remote device and its operating parameters. U.S. patent application Ser. No. 11/965,085 to Baarman et al, which is entitled “Inductive Power Supply with Device Identification” and was filed on Dec. 27, 2007, and is incorporated herein by reference. Although these are marked improvements over pre-existing systems, there is, in some applications, a desire for even greater flexibility. In some applications, there exists a desire for a single inductive power supply that is capable of providing multiple ranges of power.